Why not run a Thermostat???

[Norseman]

Being new to performance boats, I'm curious why the normal setup does not include a thermostat??
I know water is used to cool the exhaust, but it shouldn't be hard to plumb the water system so that the engine uses a thermostat and the exhaust doesn't.
Or why not restrict the water thru the engine so it warms the block more????
Wouldn't the engine run better if it was warmed up??????
Bob

[cdog]

In fact your engine will run m ore efficent at 160 deg. I have closed cooling with a 160 thermostat on a 540 ci BBC. The bad side is all the plumbing you have to do to make it work.

[seho]

As long as you have a way to relieve that water pressure in the block when the thermostat is closed, otherwise its milkshake time.

[Norseman]

As long as you have a way to relieve that water pressure in the block when the thermostat is closed, otherwise its milkshake time.
Why would it be any different than a car or truck motor???
Or am I missing something???????

[seho]

Guess I shoulda asked what kind of set up before I opened my mouth...I/O, jet drive, V-drive? Mines a jet drive so I just ASSumed thats what it was...it is monday ya know :rollside:

[riverbound]

Guess I shoulda asked what kind of set up before I opened my mouth...I/O, jet drive, V-drive? Mines a jet drive so I just ASSumed thats what it was...it is monday ya know :rollside:
I run a thermostat on my Jet and have had no problems with it.

[Hallett19]

I dont run a thermostat on my jetboat and have had no problems with it ;)

[SmokinLowriderSS]

The difference Norseman is this. A jet drive taps the high-pressure side of the drive to feed coolling water to the engine. at full throttle, that pressure could be as much as several hundred PSI, depending on just how much HP you are spinning that drive with. As long as you have enough FLOW VOLUME behind a restriction (in the inlet) then you never develop any great ammount of pressure in the block. If something reduces the water flow volume inside or after the engine, then pressure rises, and something has to give, and it won't be the iron parts. The cooling system is designed to comfortably hold up to about 20 PSI, about 30 PSI and you will start blowing gaskets (hopefully just an intake one (nice chocolatey-looking oil milkshake), head gaskets seem to cause worse troubles (hydro-lock, bent rods, bent & busted valvetrain)) :cry:
To run a thermostat, there has to be a sping-loaded bypass (relief) somewhere as well as an outlet that is fed by the relief to prevent overpressurizing the block. Some folks run them, some don't. Either system, if adjusted well, and maintained, works well. :smile:

[Norseman]

My boats a V drive, I didn't realize that a jet tapes into the high pressure side of the drive.
So if you make sure that you don't exceed 20psi pressure than a Thermostat should work OK,on any marine application, and make the engine a little more efficient, right??
Now do you still leave more clearance when assembling the engine or would you use the same clearances for bearing and rings recommended for an automotive application???
I'm thinking that you would till want to open things up a little because it's a tougher application than a car, but I'm not 100% sure.
Bob
The difference Norseman is this. A jet drive taps the high-pressure side of the drive to feed coolling water to the engine. at full throttle, that pressure could be as much as several hundred PSI, depending on just how much HP you are spinning that drive with. As long as you have enough FLOW VOLUME behind a restriction (in the inlet) then you never develop any great ammount of pressure in the block. If something reduces the water flow volume inside or after the engine, then pressure rises, and something has to give, and it won't be the iron parts. The cooling system is designed to comfortably hold up to about 20 PSI, about 30 PSI and you will start blowing gaskets (hopefully just an intake one (nice chocolatey-looking oil milkshake), head gaskets seem to cause worse troubles (hydro-lock, bent rods, bent & busted valvetrain)) :cry:
To run a thermostat, there has to be a sping-loaded bypass (relief) somewhere as well as an outlet that is fed by the relief to prevent overpressurizing the block. Some folks run them, some don't. Either system, if adjusted well, and maintained, works well. :smile: